1. Field of the Invention
The present invention relates generally to storage and information systems.
2. Description of Related Art
Large companies and other enterprises may have multiple data centers that they use to conduct their business. For example, carriers who provide phone and Internet-related services will generally have multiple geographically dispersed data centers to cover their service area. These enterprises may be running a variety of different services including voice transmission, e-mail, Internet access, messaging, video streaming, and the like, using servers and storage systems at the data centers. Thus, the effective and efficient use of resources such as the servers and storage systems in these data centers is necessary for the successful operation of these enterprises.
Server virtualization is a technology that enables server consolidation in certain information system arrangements, such as at data centers, by allowing single physical servers to provide a plurality of virtual server environments using virtual machine software. Under this technology, one or more physical servers can be divided into multiple virtual server environments instead of having multiple dedicated physical servers, each running a different server environment. Server virtualization can be used to eliminate the requirement for having a large number of different physical servers in a data center, and thereby enable more efficient use of server resources, while improving server availability. Also, server virtualization can help reduce overall costs, reduce power consumption, reduce time for server provisioning, centralize server management and administration, assist in agile service deployment and improve disaster recovery capabilities. Furthermore, in addition to server consolidation through virtualization, clustering of servers through virtualization is also becoming common in data centers for load balancing, high availability and disaster recovery. Through clustering, loads on servers can be better distributed and availability can be improved.
However, problems of coordination between server virtualization management and storage virtualization management currently exist for resource provisioning in environments including geographically-dispersed data centers. For example, using server virtualization technology, a user can migrate an application from a server at one data center to a server at another data center. This does not pose a problem from the application standpoint since the CPU resources of a server at one data center are generally interchangeable with those at another data center. However, the storage resources which contain the data used by the application also need to be made available for the migrated application.
Additionally, as server consolidation makes progress, power consumption per a certain cubic volume at data centers is increasing. Not only is the power consumed directly by CPU chips and other components becoming a concern, but also the cooling requirements for the servers, storage systems, and the like. Thus, the cost of electricity is growing to be a significant portion of the total cost of operation in some data centers. Further, the power consumption rate permitted is sometimes limited by contracts with power suppliers. Such data centers are not permitted under their contracts to use an amount of power over a specified limit, and raising the limit, will result in a higher monthly fee for the data center. Thus, data center operators need to monitor the trade off between application availability and power consumption costs.
Related art includes U.S. Pat. No. 6,854,034, to Kitamura et al., entitled “Computer System and a Method of Assigning a Storage Device to a Computer”, the disclosure of which is incorporated herein by reference. However, the prior art does not disclose a provisioning method combining server virtualization management and storage virtualization management that takes into consideration the availability of data replication and power consumption.